The present invention relates to a process for the production of an ultra-high frequency cavity resonator and to a cavity resonator obtained by this process. It more particularly applies to a construction of ultra-high frequency filters and cavity resonators for telecommunications satellites.
An ultra-high frequency cavity resonator, hereinafter called cavity, is constituted by a dielectric medium, generally air or a vacuum, surrounded by a metal envelope forming an enclosure and whose dimensions are such that an electromagnetic wave is caused to resonate within the enclosure.
In spatial construction procedures and when a high thermal stability is required, the cavities are obtained either by the mechanical assembly of parts machined from an iron-nickel alloy, or by the mechanical assembly of parts made from a metallized resin--synthetic fiber composite material. These two solutions make it possible to obtain both a low expansion coefficient and good mechanical strength.
The iron--nickel alloy cavities are heavy, which is highly disadvantageous when they are used in satellites. In order to reduce their weight, attempts have been made to reduce the thickness of the envelope, but below a certain thickness it is no longer possible to machine the cavity without causing deformation.
In the second case, the cavities made from synthetic materials, e.g. carbon fibers, have lightweight structures and particularly appropriate mechanical characteristics for the constraints imposed by the construction of satellites, but their construction costs are high.
Finally, as in both cases the filters are produced by the mechanical assembly of elementary cavities, the intersection planes to a certain extent limit the electrical performance levels.